1. Field of the Invention
The present invention relates to an orthotic insert, and more particularly for such an insert which is particularly adapted to function effectively not only in a normal gait cycle experienced in walking and forward running, but also to function effectively for strenuous athletic activities, such as high jumping or basketball, where there is very high impact loading on the foot, as well as lateral motion which would cause high lateral force loads to be exerted against the foot (e.g. in basketball).
2. BACKGROUND ART
An orthotic insert can be either soft or hard. A hard insert is a substantially rigid member, desirably having a relatively thin vertical thickness dimension and extending from the calcaneus area of the foot (the heel portion) to at least the metatarsal head area of the foot (i.e. that area at the "ball" of the foot). In general, the purpose of a rigid orthotic (sometimes called a functional orthotic) is to first position, and then to control the movements of, the midtarsal and subtalar joints during the gait cycle which the body goes through in walking and running, and also possibly for other movements.
It is believed that a clearer understanding of the background of the present invention will be achieved by first discussing generally: (a) the main components or parts of the human leg and foot and how these function relative to one another; (b) the gait cycle which a person goes through in a normal walking motion; (c) stresses placed on the foot during running, jumping and lateral movements; and (d) the intended function of a rigid orthotic in optimizing the coordinated operation of the person's foot and leg throughout the gait cycle.
For convenience, these various topics will be discussed under appropriate subheadings.